Robots are monitored in accordance with internal operating practice; and on the basis of the monitoring fault reactions are carried out; in particular, the robot is slowed down to a stationary state.
In this context, a number of different fault reactions can be carried out. Thus, it is possible to execute, in particular, a so-called STOP 0, in which mode one or more motors are immediately disconnected from an energy supply and mechanical brakes engage. However, this fault reaction has a number of drawbacks. For example, the result of such a fault reaction may be a longer decelerating path and/or a higher load on the robot. Furthermore, slowing the robot down to a stationary state during this fault reaction depends exclusively on the mechanical brake. In addition, in the course of stopping the robot, the robot may deviate from a defined path.
Therefore, a so-called STOP 1 or STOP 2 can also be carried out in accordance with internal operating practice. In this case, one or more motors act initially as the motor brakes and only subsequently are they disconnected from an energy supply (STOP 1) or remain connected to said energy supply (STOP 2). This arrangement makes it possible to shorten the decelerating path and/or to reduce the load on the robot. In addition to the mechanical brake, an additional brake is available with the motor brake, a feature that increases the reliability of the fault reaction. One advantage is that it is possible to decelerate with maximum path accuracy.
However, such a motor-active fault reaction assumes, in particular, that the corresponding motors are functioning satisfactorily. If this operational capability is not sufficiently ensured, then correspondingly when the motor-active fault reaction fails, it will be necessary to switch over to a disadvantageous reaction, for example a STOP 0, or it may even be necessary to provide said STOP 0 in advance. If the switch-over occurs on the basis of a kinematic monitoring, for example, a position-based or speed-based monitoring of the braking ramp, then this approach may give rise to the disadvantage of an extended reaction time.